Heptyl Undecylenate Bon Émollient Hydratation Heptyl Undecylenate at a glance An alkyl ester derived from castor oil Helps trap moisture, hydrating skin Leaves a light, powdery after-feel Appears in skin care in amounts between 0.01% and 26% Heptyl Undecylenate description Heptyl undecylenate is a castor oil-derived natural skin care ingredient that can help hydrate skin, prevent moisture loss and improve the feel of formulas by reducing the likelihood of a greasy after-feel. As a lightweight emollient, heptyl undecylenate lends skin a protective “shield,” trapping moisture to further prevent trans epidermal water loss (TEWL) and hydrate. Through this, heptyl undecylenate gives skin a smooth, moisturized look. It’s often used as an alternative to mineral oil or silicone. Unlike other emollients, this derivative (known as an ester) leaves a powdery, light feel on skin, not a greasy, oil one. It’s used in formulas to help mitigate the greasy feel that other hydrating emollient ingredients leave on skin. Heptyl undecylenate also serves as a solubilizer for organic sunscreen filters. The Cosmetic Ingredient Review Expert Panel concluded that heptyl undecylenate is safe for use in cosmetics, appearing in formulas at amounts ranging from 0.01% to 26%. Related ingredients: Ester